Electrical connecting devices are commonly used throughout the lighting industry for connecting electrical leads (wires) together. For example, in connecting a lighting fixture (luminaire) to a ballast, lead wires (hard wired to the ballast) are routed directly to the lamp holders located at opposite ends of the fixture. The lamp holders are typically from two to eight feet apart depending on the length of the lamp for which the fixture is designed. For example, some electrical connectors are designed primarily for fluorescent lighting and are typically located within the fluorescent light fixture. Usually, the electrical ballast comprises a long rectangular metal housing or "can" with the electrical components mounted inside. A sealant or "potting compound" is then deposited inside the can which hardens to seal the electrical components within the can. Usually also, electrical wires present in the can project through the potting material into an electrical connector for interconnection thereto by a mating to electrical connector wires of the fixture.
Such an electrical connector is known from U.S. Pat. No. 4,729,740 to Crowe in which the connector is said to be profiled for receipt within a cutout portion to seal the cavity within the housing during the curing of the potting compound. Some advantages and disadvantages of such a structure as represented by the Crowe disclosure are addressed in U.S. Pat. Nos. 5,260,678 and 5,350,316 (a continuation of Pat. No. 5,260,678), both to Wagener et al. According to the Wagener et al patents, the "picture frame" mounting of the Crowe patent results in a construction that is unacceptable requiring extra cost and assembly time to force the connector into place or to wipe away potting compound that leaks from the housing. The Wagener et al patents also address a structure in which the connector fits through a window in the sheet metal of the housing and is held in place in the housing by two "ears" which protrude through the side walls of the ballast. Although it is asserted that a good seal can be made between the connector and housing if desired and that leakage is deterred, in actuality such a structure is not leakage-proof. It has been found that such a structure as described in Wagener et al also requires extra cost and assembly time because leakage of the potting compound can and does occur due to loose fitting contact between the connector and the housing and indirect mounting of the connector to the window or cut-out in the can. Additionally, as will be discussed further hereinbelow, with reference to FIG. 10 of the Wagener et al patents, it will be seen that an external half-connector 70 is mated with an internal half-connector 50. A male pin 96e is inserted in a female contact 110e. This simple connection in practice is accompanied by misalignment problems. The pin 96e does not always fit properly in the contact 110e and full insertion is not always achieved. Such misalignment problems are a source of hidden extra costs at assembly time and also cause damage to contacts and other latent defects. Also, with reference again to FIG. 10 of the Wagener et al patents, there is disclosed a lower part of a metal wall 21 which forms a lip 21' which extends above the bottom of a hook-receiving chamber 57 formed in the half-connector and which receives a plastic hook 72 to secure the half-connector in place. This construction, before sealing, is prone to leakage and must be sealed prior to insertion in the can. In this case, sealing of the aperture to form the chamber 57 is accomplished by a sealing step or operation such as by ultrasonic welding, gluing or the like. Even after the sealing step, the structure is still prone to leakage and/or suffers from tolerance problems that result from the latching of a plastic part to a metal part.
There continues to be a need in the industry for a connecting device which includes means to exert better control over leakage of the potting compound, which avoids the problems of the prior art by providing latching of plastic part to plastic part without tolerance problems, which provides a latch chamber without the necessity of performing an additional sealing step, which is consistently substantially free of misalignment problems upon insertion of one half-connector into another half-connector, and which is suitable for purposes of ballast retrofit and ballast manufacture in terms of cost and ease of assembly.